مفردات TOEFL

periodic change in sea level mainly caused by gravitational forces

潮汐

harmful because it can poison organisms

有毒的

large waves caused by sudden displacement of water

海啸

movement of deeper water toward the ocean surface

上升流；深层海水上涌

produced by or associated with volcanoes

火山的；由火山活动形成的

water left after domestic, industrial, or other use

废水；污水

circulation of water among the atmosphere, land, and oceans

水循环

lack of enough available water to meet demand

水资源短缺

level marking the top of the saturated groundwater zone

地下水位；潜水面

land area whose water drains toward the same outlet

流域；集水区

atmospheric conditions at a particular place and time

天气

physical or chemical breakdown of rock without its transport

风化作用

unplanned fire spreading through wild vegetation

野火；林地或草地火灾

speed at which air moves past a point

风速